Aircraft



FIG. 1 is a left side perspective view of an aircraft showing my new design, the broken line illustration of the windows forms no part of the claimed design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a right side elevational view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a bottom plan view thereof; and,

FIG. 6 is a rear elevational view thereof. 

The ornamental design for an aircraft, as shown and described. 